1. Field of the Invention
The present invention relates to an image data control apparatus employed at an image-recording device which forms an image on a recording medium on the basis of image data from an external device.
2. Description of the Related Art
In conventional image-recording devices, development of technologies (printing plate exposure devices) which employ a sheet-form recording material, particularly a printing plate in which a photosensitive layer is provided on a support, and record an image on the photosensitive layer (an emulsion layer) of the printing plate with a direct laser beam or the like, by moving a recording head in an axial direction of a rotating drum (sub-scanning) while the rotating drum is rotated at high speed (main scanning) in a state in which the printing plate has been wound on a peripheral surface of the rotating drum, has been progressing. With such technologies, rapid recording of images onto printing plates is enabled.
At a time of image recording, the rotating drum is rotated using a servo motor, and rotation thereof is controlled. Image data is transmitted to the recording head synchronously with the rotation of the rotating drum.
Image data of an image to be recorded at such an image-recording device is received from an external control device such as a personal computer (below referred to as a “PC”) or the like. At this time, if the printing plate is of a positive type, it is necessary to append ablation data at an outer periphery of an image region, such that ink will not be applied at the outer periphery. Because the ablation data is a “solid” image, an increase in data volume results when the ablation data is to be created at the PC and transmitted to the image-recording device. This increase in data volume causes a reduction in image data transmission rates, resulting in adverse effects on overall operational efficiency of the image recording.
Furthermore, regardless of the kind of a printing plate (negative type or positive type), cases may arise in which, depending on a base color of a recording medium (printed matter) which is to be printed by the printing plate, it is necessary to append a predetermined color at a region other than the image region. In such a case, data for this color is transmitted from the PC, and the burden thereof is great.